Bronze colors polishing machine



May 16, 1933.

E. KRAMER BRONZE COLORSI POLISHING MACHINE Filed Oct. 50, 1950 om l@ NN 2 n l Sa mm m Rx Nm. om. MN Nm *N R mm, f. g a L u i n T- om N n m ,i F. 1 N h mm wm QN u QR Q a NT- p Patented May 16, 1933 ERWIN KRAMER, OF BERLIN, GERMANY,

PATENT OFFICE ASSIGNOR TO FIRM HARTSTOFF-METALL AKTIENGESELLSCHAFT (HAMETAG), OF BERLIN-COPENICK, .GERMANY BRONZE COLORS POLISHING MACHINE Application led ctober 30, 1930, Serial No.

My invention relates to a machine for polishing bronze colors in which the pulverulent particles to be provided with a lustre are worked by means of brushes rotating in a cylindrical drum and operating in a particular and new manner.

The polishing machines heretofore used for the treatment of bronze colors had only comparatively small dimensions and their l capacity was, therefore, correspondingly lsmall. Concerning, for instance, pulveru-A lent aluminium, only from 5 to 6 kg. could be worked at a time.

The smallness of-those machines is very i unsuited for production on a large scale, as a 'pretty large number of such machinesmust be employed which entail lconsiderable eX- pense.. Furthermore, the bronze thus attained, viz. manufactured in a plurality of l machines, is by no means as uniform as bronze produced in a large machine in which the particles are very thoroughly mixed with one another during the polishing operation.

It has, however, been found that an increase of the dimensions, especially of the diameter of the machines in question is possible only to a certain limit. To provide for the required capacity necessitates a corresponding length of the machine, say from 4 l to 6 meters or even more. Feeding these machines uniformly and emptying them quickly involves considerable difficulty, unless long, slot-like apertures in the wall of the drum and means for opening and closing these slots i mechanically are provided, but such slots constitute interruptions of the cylindrical wall of the polishing drum which interfere with the proper procedure. Moreover, the said slots givey rise to leakages which are es- -pecially detrfI/nental, if the procedure is to be carried out in the presence of an indifferent gas, as is the case, for instance, in the man- 4u factukre of aluminium bonze.

' Long drums suffer also from` the drawback that a uniform distribution of the pulverulent particles over the entire length of the drum is not attained thereby impairing the quality of the product, for the intermixing of the particles in a long drum' is not as good as in a short drum. i

492,148, and in Germany November 8, 1929.

The long length of drums of the design in question entails the necessity that the correspondingly long brushes must be subdivided,l each brush part acting, only, on a certain portion of the length of the drum.

Another point to be considered is the fact that the rifled or embossed or checkered sheet-metal plates, of which the drum -is made can be had in commercial sizes from 1 to 2 meters so that the drum must be` composed of a plurality of rings.

All these and other drawbacks of the eX- isting bronze polishing drums are obviated by the present invention which is distinguished bythe following improvements.

The long feeding and discharging slots are obviated by the features that the feeding and discharging openings are provided either only in the frontal walls of the drum, or at least in the proximity thereof.

The possibility to fill and empty the drum quickly' and to distribute the particles uniformly along the drum during the charging operation, as well as during the discharging operation, is provided for by supporting the drum in such a manner that it can assume a horizontal position, as well as an inclined one; there may be provided for this purpose particular means, as more fully 'described hereinafter. These means may be so designed that that end of the drum containing the feeding or charging aperture lies higher than the other or discharge end 'while the,

pulverulent particles are introduced into the drum, and that the reverse is the case when the finished particles are being removed from the drum, the brushes conveying the particles in either case from the' one end to the-other end. It is sufficient for the purpose' in Viewr that the angle of inclination of the drum is only small, as the brushes which rotate or circulate continuously convey the particles nevertheless quickly enough. y

The polishing procedure may last several hours. The drum may, during this time, be

inclined in the one and the other direction of.

inclination several times in order to intermingle the particles very thoroughly. The lifting and lowering the drum at one of its ends in order to effect that inclination may be done manually or mechanicallly, the respective means being in the latter case actuated by the same power that drives the brushes.

I am aware of the existence of drums that can be lifted and lowered at one end in order to give them an inclined position. Drums of that type have been used for the treatment of grain and legumes and the like, as well as for separating from one another differently shaped particles of comparatively coarse grain.

The embossed sheet-metal plates which are best suited for the walls of drums for the purpose in view can be made in thicknesses of only a few millimeters, and they are, therefore, by no means a really reliable constructive element as regards long drums, the less so, as they are subjected to a certain wear and tear which, although not particularly great, must, nevertheless, be considered, in that the sheet-metal plates become gradually thinner.

In view of these conditions it has been found advantageous to design a separate or special structure which is combined with the drum proper and ensures the proper condition of the entire arrangement and combination of parts, independent of the strength and resistibility of the drum-forming sheetmetal plates; the frontal members of the drum are to be from parts of said separate or special structure, and they arev so designed as to constitute also bearings for the shaft holding and rotating the brushes.

Furthermore, in order to provide for a uniform Contact between the inner surface of the drum wall and the brushes, these latter are subdivided into lengths corresponding about to the length of a section of the drum so thatevery brush, i. e. brush section, does not materially extend upon the neighboring ring or sections of the drum wall.

vidual sections is defective.

Finally, in order to drive the brushes in the proper manner when the drum is in an inclined position I prefer to mount the driving motor upon a separate bracket secured to the frame of the machine moving with said machinev when it is inclined maintaining the relative positions of the driving parts unchanged.

The invention is illustrated diagrammatically and by way of example on the accompanying drawing which shows an axial section through a bronze polishing machine designed according to this invention.

On the drawing, 1 and 2 denote the cast frontal ends of the drum, and 3, 4 and 5 are.

three united cylindrical sections which constitute the circumferential wall of the drum. 6, 7 and 8 are three brushes which are con- The contact be-' tween the brush or brushes is then always goed, even if the connection between the indiconnected with one another and with the frontal disks 1 and 2, as shown. These disks are connected with one another not merely by the drum wall, but also by two diametrically arranged girders 16and 17 which are also connected with the rings 11 and 14 by small brackets 43 and 44. y

The frontal disk 2 is also firmly connected with a large bracket 18 hinged by means of au axle 19 to a standard 2O mounted upon the base of the machine. Counter thereto, at the other end of the machine, the frontal disk 1 is provided with a rack 21 meshing with a pinion 24 secured to a short shaft 23 supported in a standard 22 and provided with an arm or lever 39. The drum tends to depress the rack but that is normally prevented by a pawl 25. When this pawl-is disengaged the drum can be lifted and lowered by the lifting or lowering of the rack by means of said pinion, said shaft and said arm or lever.l

Opposite the frontal disk 2, the shaft 9 is provided with a cog-wheel 26 meshing with a pinion 27 driven by the electromotor 28.

In the frontal disk 2 are two cocks 29 and 30, of which the first is located in the top of said disk below a vessel 42 whichpcontains the pulverulent bronze to be worked in the drum, whereas diametrically counter thereto, where there is the cock 30, a receptacle 31 for the finished particles is provided below said cock 30. In the example shown, the vessel 42 and the receptacle 31 are firmly connected with the drum and are inclined together with the same. I wish it, however, to be understood that said members 31 and 42 may be arranged remote from the drum, although in close proximity thereto, and may be connected by flexible tubes or hoses with the passages communicating with the plugs of said cocks.l

In the bracket 18 is supported a shaft 32 supporting in turn a loose pulley 33 driven by the electromotor 28 by means of a belt 45, and there is also provided on the shaft 32 a clutch 40/41, the part 40 of which is firmly connected with the pulley 33, whereas the part 41 is axially shiftable upon th'e shaft, but not separately rotatable upon it. When the part 41 is shifted in the direction to the pulley33 so as to meshwith the part40,thero tatory motion of the pulley 33 is transmitted to the shaft 32 and a worm 34 affixed to theV with the lever or arm 39.by a rod 38. They lengths of the arms 37 and 39 are so chosen that the arm 39 oscillates when the arms 37 rotates. Provided, the pawl be thrown out of gear and the clutch be thrown into gear, the drum will be slowly and continuously lifted and lowered, that is to say, continually inclined to the one and the other side, as long as the power is transmitted at 49/41. If such members as 32-41 are dispensed with, manual power must be applied at the arm 39 to oscillate the drum, as required. Itis also possible to maintain the drum in a certain inclination upwardly or downwardly by means of the pawl 25, the clutch 10/41 being then disengaged.

As the drum is completely closed, or can be completely closed by means of the plugs of the cocks 29 and 30, it can be filled and kept illed, with an indiferent gas which is particularly important especially if aluminium bronze is to be produced.

In order to simplify the illustration I have shown one brush in each section -of the drum Wall, but I wish it to be understood that: more than one brush, or a plurality thereof, may be employed in each section. In the embodiment shown by way of example the length of the individual brushescorresponds practically to the length of the individual drum wall sections, butit does not matter if each brush extends a little into the neighbouring section or sections, thereby preventing dead spaces occurring between the adjacent brushes. If the individual' brushes are only comparatively short, the end or elids extending into the neighbouring section or sections cannot affect the proper position of the brushes. .v

I wish it to be understood that I do not limit myself to all details. of the embodiment of the machine, as shown. There may be `=0 many departures inthe detail without depart- .the drum, whereby the fee as in such a case portions of the wall as operating parts. It

ing from the gist and essence of the invention. Thus, for instance, the pivot 19 may be located ]'ust below the drum instead of outside of an'end of the same, and the arrangement may be such that' the' weight to be balanced is more or less carried by the pivot 19 so that less power is required to incline the drum. Anyhow, the arrangement shown in the drawing presents the advantage that the movements of the frontal end 2 of the drum are only small so that the vessel 42 and the receptacle 31 can be directl connected with y ng and the ldis,- charging i s simplified.

Itis also possible to provide the feeding means at the one end of the drum and the discharging means at the other end of the same, and instead of providing the cocks or equivalents for-them in the frontal disks, said members may be arranged near the disks in the drum wall, but this is not advantageous are lost is, of course, possible to operate also in this way that only one of the two cocks is kept closed during the polishing operation whereas the other remains o en.

If the machine is so designed that the pulverulent -particles are introduced into the drum at one end of the same and are withdrawn at the other end thereof, it is also in this casepossible to retard the motion of the particles through .the drum while the polishing procedureiis going on. This retardation is eii'ected by inclining the drum in a direction so that the inletaperture is located a little lower than the outlet aperture so that the particles must travel slightly up-hill, when moving from the inlet end to the outlet end of the drum. The Obliquity of the drum may be so slight that the accumulation ofthe pulverulent particles in the same decreases in the direction from the inlet end to the outlet end so that the particles are worked upon the more intensely the nearer they are to the outlet end, i. e. to the discharge aperture.

I claim:

1. A machine for polishingthe particles of pulverulent bronze colors, comprising, in combination with a stationary drum adapted to receive said particlesv and consisting of a plurality of sections and of frontal disks connected with ne another by said sections; a' plurality of rotary brushes arranged inside the drum and contacting with the inner surface thereof and having each a length substantially corresponding to the length of said sectlons means for rotating said brushes and means for changing the normal horizontal position of the drum to an oblique position of a selected Obliquity.

2. A machine for polishing the particles of pulverulent bronze colors, comprising, in combination with a normally horizontal drum, polishin means disposedtherein, and a motorfor driving said polishing means, amechanism operatively connected with thc drum and adapted to incline it continuously and alternatingly in either direction, and means for transmitting motion from said, motor to said mechanism. v s l In testimony whereof I aiiix .my signature.

i ERWIN KRAMER. 

